2,5-dimethylhexane-2,5-di(peroxy carbonates)



United States Patent 3,225,079 2,5-DIMETHYLHEXANE-2,S-DIGPERQXYCARBONATES) James B. Harrison, Elyria, Ohio, and Orville L. Mageli,

Kenmore, N.Y., assignors to Wallace & Tiernan Incorporated, Newark, NJ.

No Drawing. Original application June 1, 1959, Ser. No. 817,094, nowPatent No. 3,117,166, dated Jan. 6, 1963. Divided and this applicationJan. 6, 1964, Ser. No. 336,028

5 Claims. (Cl. 260-463) The present invention relates to peroxyderivatives of 2,5-dimethylhexane-2,S-dihydroperoxide.

This is a division of Serial No. 817,094 filed June 1, 1959, now US.Patent No. 3,117,166, and is directed to the so-called percarbonatederivatives of 2,5-dimethylhexane-2,5-hydroperoxide.

The parent 2,5-dimethylhexane-2,5-dihydroperoxide offers interestingpossibilities as a polymerization initiator, but is not particularlysuitable for so-called high temperature operation because of itssensitivity to induced decomposition The polyfunctional 2,5dimethylhexane 2,5-dihydroperoxide offers, however, a medium from whichother polyfunctional peroxides can be prepared, such polyfunctionalperoxy compounds being suitable for use particularly as polymerizationinitiators or the so-called polymerization initiators or the so-calledpolymerization catalysts.

It has been found that the products of the present invention do notsuffer from the defect of the parent.

When the polyfunctional hydroperoxide2,5-dimethylhexane-2,S-dihydroperoxide is reacted with a haloformate orrelated material, a precarbonate is the resultant product, thepercarbonates differing from esters, R'COR, where R is the peroxyradical of 2,5-dimethylhexane-2,5- dihydroperoxide, and R is the radicalfrom the employed acid chloride or anhydride, while the percarbonatesare R"COOR, wherein R may be a saturated aliphatic group of from 1 to 11carbon atoms inclusive, e.g., lower alkyl, and halogen-substituted alkylradicals, as for instance ClCH The reaction to produce the percarbonate,as for instance, by reaction of one molar quantity of2,5-dimethylhexane-2,S-dihydroperoxide with two molar quantities of ofethylchloroformate will produce the percarbonate as shown in thespecific example as follows:

2, 5-dimethylhexane2, 5-di(peroxyethylcarbo ate) Where stoichiometricquantities of reactants are chosen, as indicated above, based upon thepresence of two hydroperoxide groups in the parent compound, thediperoxy derivatives are the end result. If it be desired to produce themonoderivative, one-half of the stoichiometric amount of reactantrequired to react with all of the hydroperoxide groups is chosen as thereactant, and it is suggested that the reaction preferably, under suchcircumstances, be carried out in an inert organic solvent. Havingprepared initially a mono-derivative containing a tree hydroperoxidegroup, a mixed derivative can thereafter be prepared from suchmonoderivative.

The new products of the present invention are either solids or highboiling point oils which possess particular efficacy as initiators ofpolymerization reactions, depending upon polymerization by reason of thepresence of 3,225,079 Patented Dec. 21, 1965 ethylenic unsaturation, asfor instance in vinyl compounds and in the polyester materials, each ofwhich possesses vinyl or ethylenic unsaturation. In the case of thevinyl compounds, exceptionally clear, colorless, and nondarkeningproducts result.

The following examples are given as specific illustrations ofrepresentative compounds prepared within the scope of the invention andare not to be deemed as limitative of the invention. In substantiallyall instances, the active oxygen content was determined by acceptedstandard procedures, as for instance, by potassium iodide thiosulfatetitration; by ultimate analysis for carbon and hydrogen; or by molecularrefraction and, in some instances; some or all of these testingtechniques were employed.

In Example 1 immediately below, there is described a suggested procedurefor preparing the parent dihydroperoxide in excellent yield and ofexceptional purity after one recrystallization:

Example 1 .2,5-dimethylhexane-Z,5-dihydr0per0xia'e To 462 gm. (6.8moles) of 50% hydrogen peroxide was gradually added, over a period of 30minutes, 434 gm. of 77% sulfuric acid with vigorous stirring. Thetemperature was kept at 10 C. Then a 100 gm. (0.69 mole) of2,5dimethylhexanediol-2,5 was added to the acid-hydrogen peroxidemixture in a single dose. Stirring was continued at 10 C. for 10minutes, then gradually warmed up to room temperature and continued foran additional hour.

The crude dihydroperoxide was washed first with 100 ml. of unsaturatedammonium sulfate solution and then with two washings of 100 ml. portionsof appropriate salt. The last washing had a pH of 5 and showed noreaction with catalase. After drying overnight in a Stokes dryer, theproduct weighed 103 gms. (82% yield, 16% active oxygen).Recrystallization from benzene yielded 90 gms. with 17.6% active oxygen(98% purity).

Example 2.--2,5-dimethylhexane-2,5-di(peroxy ethyl carbonate) To a cold(0 C.) solution containing 9 g. (0.05 mole) of the dihydroperoxide, ml.of ethyl ether and 12 ml. (0.15 mole) of pyridine was slowly added 11 g.(0.1 mole) ethyl chlorocarbonate. The addition period of 15 minutes wasfollowed by an additional 15 minute stirring period. The reactionmixture was then filtered to remove solid pyridine hydrochloride. Theethereal solution was thoroughly washed, then dried over anhydrousmagnesium sulfate. Removal of the ether under reduced pressure left acolorless, sweet-smelling oil.

n l.4423. d 1.067.

Calculated for C H O C, 52.16%; H, 8.13%; MR 76.70; active oxygen,9.93%. Found: C, 53.08%; H, 8.70%; MR 79.60; active oxygen, 9.80%.

Example 3.--2,5-dimethylhexane-2,5-di(per0xy betachloroethyl carbonate)To a cold (0 C.) solution containing 9 g. (0.05 mole) of thedihydroperoxide, 80 ml. of ethyl ether and 12 ml. (0.15 mole) ofpyridine was slowly added 14.3 g. (0.1 mole) beta-chloroethylchlorocarbonate. The addition period of 15 minutes was followed by anadditional 15 minute stirring period. The reaction mixture was filteredto remove solid pyridine hydrochloride. The ethereal solution wasthoroughly washed, then dried over anhydrous magnesium sulfate. Removalof the ether under reduced pressure left a colorless liquid.

Calculated for C H O Cl MR 87.76; active oxygen, 8.19%. Found: MR 90.70;active oxygen, 7.90%.

3 Example 4.2,5-dimethylhexane-2,5-di(peroxy isobutyl carbonate) To acold (0 C.) solution containing 9 g. (0.05 mole) of the dihydroperoxide,80 ml. of ethyl ether and 12 ml. (0.15 mole) of pyridine was slowlyadded 13.7 g. (0.1 mole) isobutyl chlorocarbonate. The addition periodof 15 minutes was followed by an additional 15 minute stirring period.The reaction mixture was then filtered to remove solid pyridinehydrochloride. The etheral solution was thoroughly washed, then driedover anhydrous magnesium sulfate. Removal of the ether under reducedpressure left a slightly yellowish liquid.

Calculated for C H 0 Found: active oxygen 6.44%.

What is claimed is:

1. A percarbonate of the formula:

active oxygen, 8.46%.

where R is 0 R COR 9 and R is a lower alkyl radical.

3. 2,5-dirnethylhexane-2,5-di(peroxyethyl carbonate).

4. 2,5-dimethylhexane-2,S-di(peroxy beta chloro ethyl carbonate).

5. 2,5 dimethylhexane 2,5 di(peroxy isobutyl car bonate).

References Cited by the Examiner UNITED STATES PATENTS 2,374,789 5/1945Strain 260-463 X CHARLES B. PARKER, Primary Examiner.

FLOYD D. HIGEL, Assistant Examiner.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3225,079 December 21, 1965 James B. Harrison et al.

It is hereby certified that error appears in the above numbered patentrequiring correction and that the said Letters Patent should read ascorrected below.

Column 1, line 28, strike out "initiators or the so-calledpolymerization"; line 34, for "precarbonate" read percarbonate line 45,strike out "of"; same column 1, lines 47 to 55, for that portion of theformula reading CLC- c H c1c-o(c H I O 2 5 read 2 5 column 2, line 14,the semicolon should be a comma; line 65, before "filtered" insert thencolumn 3, line 9, for

"etheral" read ethereal Signed and sealed this 29th day of November1966.

(SEAL) Attest:

ERNEST W. SWIDER EDWARD J. BRENNER Attesting Officer Commissioner ofPatents

1. A PERCARBONATE OF THE FORMULA: